1. Field of the Invention
This invention relates to a modular body support system for a prone, supine or sidelying person utilizing a support which may be in the form of an elongated frame with independently acting inserts and having an optional oversized cover for use thereon. The system is specifically suited for bed confined patients to prevent tissue trauma.
2. Description of the Prior Art
When a patient in a hospital or convalescent home is required to lay in bed for long periods of time various ways have been devised in an endeavor to find comfort for the person and also to prevent tissue trauma. Tissue trauma may be in the form of decubitus ulcers, ischemic ulcers, bedsores, etc.
Heretofore, mattress designers endeavored to help the patient by constructing a mattress with springs of different compression strength while others have included foam coverings, or overlays endeavoring to reduce discomfort. These developments have not been successful because they do not negate large concentrated loads and when a sufficiently large external force of a support surface is applied against the skin of a patient the skin's supporting infra structure will unsuccessfully attempt to infuse the contracted skin area with blood. If the blood supply is constrained by forces bearing on the vessels or capillaries for any appreciable time, tissue will weaken die and tissue trauma results.
Additional efforts have been made to design overlays and mattresses by utilizing urethane foam of differing density and thickness dependent upon what part of the body will rest thereon. The disadvantage of such structure is that with a solid piece of foam, body weight causing indentation such as a hip bone, etc. will roll the foam into a depression or indentation causing stretching thereof and unwanted friction and pressure contact with the skin area.
In U.S. Pat. No. 3,197,357 issued to K. H. N. Schulper the inventor discloses a mat, pad or mattress formed of convoluted foam. This structure has assisted to some extent in allowing air to pass beneath a body laying thereon. However, as with the previous described construction the convolutions were not completely successful because again the surface do not adequately distribute large concentrated loads.
To some extent this stretching has been overcome by U.S. Pat. No. 4,706,313 to Murphy. Here the inventor provides cutouts in a block of foam that do not go through the structure but stop before the bottom surface thereof. The cutouts are preferably filled with foam or the foam may be let out creating a void for various parts of the human body. In addition, the patent calls for a bloused oversheet or cover which encases the entire structure. Such a construction creates an undue amount of time to change the cover. The block must be lifted up and the cover unzipped and slide off from around the block. Further the cover consists of a foam sheet and a top sheet. The foam sheet is recited as being preferably one inch in thickness. Such structure would create a hammock effect suspended over the openings which is not desired. Further, with the foam sheet contacting the foam mattress or inserts an extremely high coefficient of friction is created which is not desired. Finally, there is the disadvantage of the cutouts being large and the inserts also being large to fit within the cut outs. Such large pieces of foam do not furnish the desired compression relief for the various parts of the body.
Applicant's are also aware of the patent to Blair, U.S. Pat. No. 3,893,198. This patent is directed to a support structure having individual load bearing foam sections as well as a taut cover. Such a cover defeats the purpose of the individual load bearing units and creates an ordinary solid support fraught with the earlier prior art problems.